Plate valve

ABSTRACT

A plate valve especially adapted for use in reciprocating compressors and comprising a valve seat, a valve guard spaced from the valve seat, a valve plate serving as a closing member, and a damping plate interposed between the valve plate and the valve guard.

United States Patent 9 Bauer et al. 1 1 Nov. 28, 1972 r [54] PLATE VALVE[56]. References Cited [72] Inventors: Friedrich Ballet, Vienna,-Austria; UNITED STATES PATENTS Robert Kohler, Schongau/Lech, 1 Germany1,316,184 9/1919 Prellwuz ..l37/5l6.13 3,177,893 4/1965 King ..l37/514 X1 um lioerbiser Yenfllwerlw Akfien- 2,870,783 1/1959 Kehler ..l37/516.13

E Vienna, Austria 3,369,563 2/1968 Deminger ..l37/514 2 390 527 12/1945Flint ..l37/514 X 22 F] d. F b. 17 1971 l 1 e e 3,265,085 8/1966 Koehler..l37/5l6.13 x [21] Appl. No.: 116,149

. Primary Examiner-Robert G. Nilson [30] Foreign Application PriorityData AttorneyWats0n, C0le, Grmdle & Watson Feb. 18, 1972 Austria ..A1449/70 [57] ABSTRACT A plate valve especially adaptedfor use inreciprocat- ..137/5 14, 137/516.1F sl,6l:Z/55/(2,g ingcompressors andcomprising a valve seat, a valve Fie'ld 1 3 516 ll guard spaced from thevalve seat, a valve plate servm'g 5 17 21 23 as a closmg member, and adampmg plate mterposed a v between the valve plate and the valve guard.

V 6 Clains, 3 Drawing fi ures I I 1' I [Zia PLATE VALVE The inventionrelates to a plate'valve particularly for reciprocating compressors, theplate valve being of the kind having a valve seat and a valve guardbetween which a spring loaded valve plate covering the flow passages inthe valve seat and at least one damping plate, are arranged, the valveplateconsisting of concentric rings connected by radial webs.

In plate valves, as is well known, the plates interposed between thevalve seat and the valve guard move with the compressor cycle andimpinge upon the valve guard and valve seat at relatively high speeds,thus subjecting them to high stresses. Moreover, the highest stresses inthe valve plate occur when the plate does not impinge upon thestroke-limiting surfaces with its entire surface at the same time, buttumbles and impinges upon the valve guard or valve seat with its outeredge first. Because of these edge impacts, the outer ring of the valveplate is exposed to the greatest danger of breaking. For damping theopening impacts of the valve plate, damping plates are already knownwhich are arranged between the valve seat and the valve guard to cushionthe impacts of the valve plate during opening of the valve. But evenwith damping plates the desired result cannot always be achieved. Forexample in reciprocating compressors with oil lubrication, a film of oilis formed on the plates. Although on the one hand this results in anadditional damping effect, it leads on the other hand to an undesirableadherance of the plates to each other. Consequently, the closing processof the valve plate is retarded resulting in increased impact stressesduring closure of the valve. In addition, the retarded closure of thevalves decreases the output of the compressor.

The present invention provides a plate valve including a valve seat, avalve guard, and a spring loaded valve plate consisting of an outer ringand an inner ring or rings, the rings being connected by radial webs andthe valve plate being interposed between the valve seat and the valveguard wherein at least one damping plate is provided between the valveplate and the valve guard, the outer diameter of the or each dampingplate being smaller than the outer diameter of the valve plate and aradially outer zone of the damping platebeing positioned over the or oneof the inner rings of the valve plate.

The valve plate may have a plurality of inner rings and the dampingplate has radial zones over each said inner ring.

In this realization the impact load during the opening movement of thevalve plate is substantially absorbed by the inner rings of the same,which impinges upon the damping plate, thus the outer ring of the valveplate can swing out freely, and is consequently subjected to lessstress. In addition, the effect of adhesion is reduced, as the outerring of the valve plate is not incontact with the damping plate, and theeffective contact surface is reduced respectively, whereby the valveplate is furthermore subjected to less stress during the closingmovement.

Spring means for the valve plate, such as coil springs or the springarms of a spring plate, may be positioned radially outwardly of theouter periphery'of the damping plate. Recesses in the damping plate forthe springs thereby becoming unnecessary which simplifies themanufacture of the damping plate.

The damping plate may be slightly dish-shaped. Separate damping springsmay then not be required. Preferably, two dish-shaped damping plates inopposite directions may be used.

The invention is now described, by way of example, with reference to theaccompanying drawings showing cross-sectional views of three embodimentsof the invention.

FIG. 1 shows a plate valve according to one embodiment' of theinvention;

FIG. 2 shows a plate valve according to another em bodiment of theinvention; and I FIG. 3 shows a plate valve according to yet anotherembodiment of the invention.

Referring to FIG. 1, the plate valve according to the invention consistsof a valve seat 1, with a valve plate 2,

and a damping plate 3 disposed above. Both plates are held in a centeredposition by a guide ring 4, which is stepped in order to support thedamping plate 3 spaced from the valve plate 2 when the valve is closed.Above the damping plate 3, a valve guard 5 is provided which limits thestroke of the plates during the opening movement. The individual partsof the valve are clamped together by a central screw 6 with a nut 7. Theload spring for the valve plate 2 consists in this embodiment of coilsprings 8 which are supported in the valve guard 5 in a spring seat andin the known manner act upon the valve plate 2 through recesses in thedamping plate 3. In addition further spring seats are provided in valveguard 5 for damping springs 9 supporting the damping plate 3 spaced fromthe valve guard 5. 1

As can be seen from the drawing, the damping plate 3 has a smallerdiameter than the valve plate 2. The ontermost ring of the damping plate3 is positioned above the second ring of the valve plate 2. Therefore,during the opening movement of the valve plate 2, not the outer marginof the outermost ring, but the second ring of the valve plate 2 impingeson the damping plate 3. Thereby the outer edge of the valve plate 2,which according to experience is mostly exposed to the danger ofbreaking; is not subjected to excessive impact stresses, whilst theopening impacts of the valve plate are nevertheless intercepted to asubstantially undiminished degree by the damping plate 3. In addition,the adhesiveness occurring in lubricated valves by the presence of anoil film between the plates is diminished, as'there is no outer ring forthe damping plate 3 and the area of contact between the valve plate 2and the damping plate 3 is correspondingly smaller. Moreover, in theopened valve the outermost ring of the valve plate 2 is spaced from thevalve guard 5 by a distance detemiined by the thickness of the dampingplate 3, whereby a gap is formed between the valve guard 5 and the outerring of the valve plate2. Medium flowing back through the flow channelsin the valve guard 5 penetrates into this gap providing an additionalclosing force on the valve plate 2 such, that the valve plate 2, evenwith high deposition of oil on the plates, is

loosened from the valve guard and the damping plate 3 and faster closingof the valve is facilitated.

The valve shown in FIG. 2 is substantially similar to the arrangement inFIG. 1, with one exception that the loading spring of the valve plate 2consists of a spring plate 10 with spring arms 11 bent out of the planeof the spring plate. The spring plate 10 is retained with its innermostring serving as a hub between the valve guard 5 and the guide ring 4.The spring arms are formed by the outermost ring of the spring plate andthus are positioned outside the periphery of the damping plate 3.Recesses in the damping plate 3 for the.

spring arms 1] become thereby unnecessary.

In the embodiment according to FIG. 3, two damping plates 3 are providedwhich are curved in opposite directions and are in contact with eachother along their inner margins. In this embodiment too, the damp ingplates 3 have a substantially smaller outer diameter than the valveplate 2.such that the outermost ring of the valve plate 2 is positionedentirely outside the periphery of the damping plates 3. Because of thedishshaped form of the damping plates 3, additional springs for thesemay not be required, as they are held apart by their inherent elasticityfrom the valve guard when the valve is closed. The reduced outerdiameter of the damping plate results in a reduction of the resistanceto flow at the outer periphery of the valve in the region of theoutermost plate ring of the valve plate 2.

We claim:

1. A plate valve including a valve seat, a valve guard, and a springloaded valve plate consisting of an outer ring and at least one innerring, the rings being connected by radial webs and the valve plate beinginterposed between the valve seat and the valve guard wherein at leastone damping plate is provided between the valve plate and the valveguard, the outer diameter of the damping plate being smaller than theouter diameter of the valve plate and a radially outer zone of thedamping plate being positioned over an inner ring of the valve plate,and including means for holding the damping plate freely spaced at adistance both from the valve plate and the valve guard when the valve'is closed.

2. A plate valve according to claim 1, wherein the valve plate has aplurality of inner rings and the damping plate has a radial zone overeach of said inner rings.

3. A plate valve according to claim 1, wherein spring means for thevalve plate are positioned radially outwardly of the outer periphery ofthe damping plate.

4. A plate valve according to claim 3, wherein said spring means arecoil springs.

5. A plate valve according to claim 3, wherein said spring means arespring arms of a spring plate.

6. A plate valve according to claim 1, wherein the damping plate isdish-shaped.

1. A plate valve including a valve seat, a valve guard, and a springloaded valve plate consisting of an outer ring and at least one innerring, the rings being connected by radial webs and the valve plate beinginterposed between the valve seat and the valve guard wherein at leastone damping plate is provided between the valve plate and the valveguard, the outer diameter of the damping plate being smaller than theouter diameter of the valve plate and a radially outer zone of thedamping plate being positioned over an inner ring of the valve plate,and including means for holding the damping plate freely spaced at adistance both from the valve plate and the valve guard when the valve isclosed.
 2. A plate valve according to claim 1, wherein the valve platehas a plurality of inner rings and the damping plate has a radial zoneover each of said inner rings.
 3. A plate valve according to claim 1,wherein spring means for the valve plate are positioned radiallyoutwardly of the outer periphery of the damping plate.
 4. A plate valveaccording to claim 3, wherein said spring means are coil springs.
 5. Aplate valve according to claim 3, wherein said spring means are springarms of a spring plate.
 6. A plate valve according to claim 1, whereinthe damping plate is dish-shaped.